Electronic device

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2017-49556, filed on Mar. 15, 2017, the entire contents of which are incorporated herein by reference.

The present disclosure relates to an electronic device.

A conventional semiconductor light emitting device includes a base, a semiconductor light emitting element, a wiring pattern, a bonding layer, and a sealing resin. The wiring pattern is formed on the base. The semiconductor light emitting element is disposed on the wiring pattern via the bonding layer. The sealing resin is disposed on the base so as to cover the semiconductor light emitting element and the wiring pattern.

Some embodiments of the present disclosure provide an electronic device capable of preventing a bonding layer from peeling from a wiring pattern or a base.

According to one embodiment of the present disclosure, there is provided an electronic device including: a base; a wiring pattern formed on the base; an electronic element disposed on the wiring pattern; and a bonding layer interposed between the electronic element and the wiring pattern, wherein an opening is formed in the wiring pattern and the bonding layer is in contact with a portion of the base exposed by the opening in the wiring pattern.

Other features and advantages of the present disclosure will become more apparent from the following detailed description in conjunction with the accompanying drawings.

FIG. 1 is a perspective view of an electronic device according to a first embodiment.

FIG. 2 is a front view of the electronic device according to the first embodiment.

FIG. 3 is a left side view of the electronic device according to the first embodiment.

FIG. 4 is a right side view of the electronic device according to the first embodiment.

FIG. 5 is a plan view of the electronic device according to the first embodiment.

FIG. 6 is a view in which an electronic element, a wire, and a protective layer are excluded from the electronic device shown in FIG. 5 .

FIG. 7 is a view in which a bonding layer is excluded from the electronic device shown in FIG. 6 .

FIG. 8 is a bottom view of the electronic device according to the first embodiment.

FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 5 .

FIG. 10 is a cross-sectional view taken along line X-X in FIG. 5 .

FIG. 11 is a plan view of an electronic device at a certain point of time in a method of manufacturing the electronic device according to the first embodiment.

FIG. 12 is a plan view of an electronic device at a certain point of time in the method of manufacturing the electronic device according to the first embodiment.

FIG. 13 is a plan view of an electronic device at a certain point of time in the method of manufacturing the electronic device according to the first embodiment.

FIG. 14 is a plan view of an electronic device according to a second embodiment.

FIG. 15 is a plan view of an electronic device according to a third embodiment.

Embodiments of the present disclosure will be now described in detail with reference to the drawings.

First Embodiment

A first embodiment will be described below with reference to FIGS. 1 to 13 .

FIG. 1 is a perspective view of an electronic device according to a first embodiment. FIG. 2 is a front view of the electronic device according to the first embodiment. FIG. 3 is a left side view of the electronic device according to the first embodiment. FIG. 4 is a right side view of the electronic device according to the first embodiment. FIG. 5 is a plan view of the electronic device according to the first embodiment.

An electronic device A 1 shown in these figures includes a base 1 , a wiring pattern 3 , an electronic element 41 , a wire 42 , a bonding layer 5 , a protective layer 6 , and a resin portion 7 . The resin portion 7 is not shown in FIG. 5 .

The base 1 is made of, e.g., insulating material such as insulating resin or ceramic. An example of the insulating resin may include glass epoxy resin or the like. An example of the ceramic may include Al 2 O 3 , SiC, AlN, or the like. The base 1 may be a substrate on which an insulating film made of metal such as aluminum is formed. The base 1 has a rectangular shape when viewed in a thickness direction Z 1 of the base 1 .

The base 1 has a main surface 11 , a back surface 13 , a first side surface 15 A, a second side surface 15 B, a third side surface 15 C, and a fourth side surface 15 D.

The main surface 11 and the back surface 13 are separated from each other in the thickness direction Z 1 of the base 1 and face opposite directions. Both the main surface 11 and the back surface 13 are flat.

The first side surface 15 A and the second side surface 15 B are separated from each other in a first direction X 1 and face opposite directions. Both the first side surface 15 A and the second side surface 15 B are connected to the main surface 11 and the back surface 13 . Both the first side surface 15 A and the second side surface 15 B are flat.

A first concave portion 16 A and a second concave portion 16 B are formed in the base 1 . The first concave portion 16 A and the second concave portion 16 B are recessed inwardly from the first side surface 15 A and the second side surface 15 B of the base 1 , respectively. Both the first concave portion 16 A and the second concave portion 16 B are formed to span from the main surface 11 to the back surface 13 . In the first embodiment, the first concave portion 16 A and the second concave portion 16 B have a semicircular shape when viewed in the thickness direction Z 1 of the base 1 .

The third side surface 15 C and the fourth side surface 15 D are separated from each other in a second direction Y 1 and face opposite directions. Both the third side surface 15 C and the fourth side surface 15 D are connected to the main surface 11 and the back surface 13 . Both the third side surface 15 C and the fourth side surface 15 D are flat.

FIG. 6 is a view in which an electronic element, a wire, and a protective layer are excluded from the electronic device shown in FIG. 5 . FIG. 7 is a view in which a bonding layer is excluded from the electronic device shown in FIG. 6 . FIG. 8 is a bottom view of the electronic device according to the first embodiment.

The wiring pattern 3 shown in FIG. 5 to FIG. 7 defines a current path through which electric power is supplied to the electronic element 41 . The wiring pattern 3 is electrically connected to the electronic element 41 . The wiring pattern 3 is made of, e.g., metal such as Cu, Ni, Ti, Au, or the like alone or in combination. The wiring pattern 3 is formed on the base 1 . In the first embodiment, the wiring pattern 3 is formed by plating Au on Cu. The material of the wiring pattern 3 is not particularly limited to those mentioned here. The wiring pattern 3 is formed on the main surface 11 and the back surface 13 . In the first embodiment, the wiring pattern 3 is formed in the first concave portion 16 A and the second concave portion 16 B.

The wiring pattern 3 includes a die pad portion 31 , a first conductive portion 32 , a second conductive portion 33 , a first edge portion 35 A, a second edge portion 35 B, a first connecting portion 36 A, a second connecting portion 36 B, a first side surface portion 37 A, a second side surface portion 37 B, a first back surface portion 38 A, and a second back surface portion 38 B. An opening 39 is formed in the wiring pattern 3 .

FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 5 . FIG. 10 is a cross-sectional view taken along line X-X in FIG. 5 .

In the first embodiment, the opening 39 has an annular shape (more specifically, an annular shape with a portion missed). The bonding layer 5 is disposed in the opening 39 . As shown in FIG. 10 , the bonding layer 5 is in contact with a portion 119 of the base 1 exposed by the opening 39 in the wiring pattern 3 .

As shown in FIGS. 5 to 7 and FIGS. 9 and 10 , the die pad portion 31 , the first conductive portion 32 , the second conductive portion 33 , the first edge portion 35 A, the second edge portion 35 B, the first connecting portion 36 A, and the second connecting portion 36 B are formed on the main surface 11 of the base 1 .

The electronic element 41 is disposed on the die pad portion 31 . A part of the die pad portion 31 defines the opening 39 . The bonding layer 5 is in contact with the die pad portion 31 . The die pad portion 31 includes a first inner side surface 311 facing a direction intersecting the thickness direction Z 1 of the base 1 (a direction perpendicular to the thickness direction Z 1 in the first embodiment). The first inner side surface 311 defines a part of the opening 39 . In the first embodiment, the bonding layer 5 is in contact with the first inner side surface 311 . As shown in FIG. 7 , the die pad portion 31 includes a first edge 31 A and a second edge 31 B located opposite to each other in the die pad portion 31 when viewed in the thickness direction Z 1 of the base 1 .

The first conductive portion 32 is separated from the die pad portion 31 . In the first embodiment, the first conductive portion 32 is annular and surrounds the die pad portion 31 . More specifically, the first conductive portion 32 is in an annular form having a rectangular outer shape. The outer shape of the first conductive portion 32 is not limited to the rectangular shape but may be other shapes such as a circular shape and a triangular shape. A part of the first conductive portion 32 defines the opening 39 . When viewed in the thickness direction Z 1 of the base 1 , the opening 39 is interposed between the first conductive portion 32 and the die pad portion 31 . The bonding layer 5 is in contact with the first conductive portion 32 .

As shown in FIG. 10 , the first conductive portion 32 includes a second inner side surface 321 facing the first inner side surface 311 . The second inner side surface 321 has an arc shape when viewed in the thickness direction Z 1 . The bonding layer 5 is in contact with the second inner side surface 321 . Unlike the first embodiment, the second inner side surface 321 may not be in contact with the bonding layer 5 but may be separated from the bonding layer 5 . The first conductive portion 32 has a front surface 322 facing the thickness direction Z 1 of the base 1 . The front surface 322 of the first conductive portion 32 has a contact part 322 A and an exposed part 322 B. The contact part 322 A is in contact with the bonding layer 5 . The exposed part 322 B is exposed from the bonding layer 5 . The contact part 322 A is located between the exposed part 322 B and the opening 39 when viewed in the thickness direction Z 1 of the base 1 . As shown in FIG. 7 , in the first embodiment, a distance L 2 between the second inner side surface 321 and the first inner side surface 311 is substantially equal to a distance L 1 . However, the distance L 2 may be smaller or larger than the distance L 1 . In the first embodiment, the distance L 2 is larger than a width W 1 of the second conductive portion 33 . For example, the distance L 1 may be larger than the distance L 2 and the distance L 2 may be larger than the width W 1 . When the distances L 1 and L 2 are larger than the width W 1 , this means that the width of a portion (the second conductive portion 33 ) connecting the die pad portion 31 is small, thereby limiting the possibility of the die pad portion 31 from peeling. Since the distance L 2 is smaller than the distance L 1 , a force of lifting the electronic element 41 at the time of application of a thermal stress or the like becomes small, reducing the likelihood of the electronic element 41 from slipping out.

As shown in FIG. 7 , the second conductive portion 33 is connected to both the die pad portion 31 and the first conductive portion 32 . The second conductive portion 33 is located between the die pad portion 31 and the first conductive portion 32 . A part of the second conductive portion 33 defines the opening 39 . The bonding layer 5 is in contact with the second conductive portion 33 . The second conductive portion 33 extends from the die pad portion 31 toward the first conductive portion 32 when viewed in the thickness direction Z 1 of the base 1 . Specifically, the second conductive portion 33 is disposed on a side opposite the first edge portion 35 A with respect to the die pad portion 31 . The second conductive portion 33 has a front surface 332 facing the thickness direction Z 1 of the base 1 . The front surface 332 of the second conductive portion 33 is in contact with the bonding layer 5 . In the first embodiment, the entire front surface 332 is in contact with the bonding layer 5 . In the first embodiment, the width W 1 of the second conductive portion 33 is smaller than the separation distance L 1 between the first edge 31 A and the second edge 31 B. Unlike the first embodiment, the width W 1 of the second conductive portion 33 may be equal to or greater than the separation distance L 1 between the first edge 31 A and the second edge 31 B.

Unlike the first embodiment, the second conductive portion 33 may not be formed. The die pad portion 31 may be insulated from any other portion of the wiring pattern 3 . In this case, the opening 39 may have a completely annular shape rather than the partial annular shape.

As shown in FIG. 7 , the first edge portion 35 A extends along an edge 161 A of the first concave portion 16 A. In the first embodiment, the first edge portion 35 A is semi-annular. The first connecting portion 36 A is located between the first conductive portion 32 and the first edge portion 35 A and is electrically connected to the first conductive portion 32 and the first edge portion 35 A. More specifically, the first connecting portion 36 A is connected to the first conductive portion 32 and the first edge portion 35 A.

The wire 42 is bonded to a wire bonding pad portion 34 . The wire bonding pad portion 34 is separated from the die pad portion 31 in the first direction X 1 .

The second edge portion 35 B extends along an edge 161 B of the second concave portion 16 B. In the first embodiment, the second edge portion 35 B is semi-annular. The second connecting portion 36 B is located between the wire bonding pad portion 34 and the second edge portion 35 B and is electrically connected to the wire bonding pad portion 34 and the second edge portion 35 B. More specifically, the second connecting portion 36 B is connected to the wire bonding pad portion 34 and the second edge portion 35 B.

In the first embodiment, the wiring pattern 3 includes a conductive portion 36 C. The conductive portion 36 C extends along the second direction Y 1 and reaches the third side surface 15 C and the fourth side surface 15 D. The conductive portion 36 C is connected to the wire bonding pad portion 34 and the second connecting portion 36 B.

The first side surface portion 37 A is formed on the inner surface of the first concave portion 16 A and is connected to the first edge portion 35 A. The second side surface portion 37 B is formed on the inner surface of the second concave portion 16 B and is connected to the second edge portion 35 B.

As shown in FIG. 8 , the first back surface portion 38 A and the second back surface portion 38 B are formed on the back surface 13 of the base 1 .

The first back surface portion 38 A is connected to the first side surface portion 37 A. The first back surface portion 38 A includes edges 381 A to 387 A. The edge 381 A extends along the first direction X 1 . The edge 382 A extends along the second direction Y 1 and is connected to the edge 381 A. The edge 383 A extends along the first direction X 1 and is connected to the edge 382 A. The edge 384 A extends along the second direction Y 1 and is connected to the edge 381 A. The edge 384 A is shorter than the edge 382 A. The edge 385 A is a circular-arc shape and is connected to the edge 384 A. The edge 385 A reaches an end of the back surface 13 of the base 1 in the first direction X 1 . The edge 386 A extends along the second direction Y 1 and is connected to the edge 383 A. The edge 386 A is shorter than the edge 382 A. The edge 387 A is a circular-arc shape and is connected to the edge 386 A. The edge 387 A reaches the end of the back surface 13 of the base 1 in the first direction X 1 .

The second back surface portion 38 B is connected to the second side surface portion 37 B. The second back surface portion 38 B includes edges 381 B to 387 B. The edge 381 B extends along the first direction X 1 . The edge 382 B extends along the second direction Y 1 and is connected to the edge 381 B. The edge 383 B extends along the first direction X 1 and is connected to the edge 382 B. The edge 384 B extends along the second direction Y 1 and is connected to the edge 381 B. The edge 384 B is shorter than the edge 382 B. The edge 385 B is a circular-arc shape and is connected to the edge 384 B. The edge 385 B reaches an end of the back surface 13 of the base 1 in the first direction X 1 . The edge 386 B extends along the second direction Y 1 and is connected to the edge 383 B. The edge 386 B is shorter than the edge 382 B. The edge 387 B is a circular-arc shape and is connected to the edge 386 B. The edge 387 B reaches the end of the back surface 13 of the base 1 in the first direction X 1 .

The electronic element 41 is disposed on the die pad portion 31 of the wiring pattern 3 . In the first embodiment, the electronic element 41 is a semiconductor element, more specifically an optical element including a light emitting element and a light receiving element. In the first embodiment, the electronic element 41 is a light emitting element and serves as a light source of the electronic device A 1 . In the first embodiment, the electronic element 41 is an LED chip. In the first embodiment, the electronic element 41 includes an n-type semiconductor layer, an active layer, and a p-type semiconductor layer. The n-type semiconductor layer is laminated on the active layer. The active layer is laminated on the p-type semiconductor layer. Therefore, the active layer is located between the n-type semiconductor layer and the p-type semiconductor layer. The n-type semiconductor layer, the active layer, and the p-type semiconductor layer are made of, e.g., GaN. The electronic element 41 includes a main surface electrode pad (not shown) and a back surface electrode pad (not shown) facing opposite directions. The electronic element 41 is mounted on the base 1 . The emission color of the electronic element 41 is not particularly limited.

Unlike the first embodiment, the electronic element 41 need not be an optical element. For example, the electronic element 41 may be an element (for example, a Zener diode or an IC chip) that does not perform an optical function. The electronic element 41 need not be a semiconductor element. For example, the electronic element 41 may be a resistor or a capacitor.

The wire 42 is bonded to the electronic element 41 and the wire bonding pad portion 34 . The wire 42 is made of a conductive material. The wire 42 makes electrical conduction with the electronic element 41 and the wire bonding pad portion 34 . In the first embodiment, the wire 42 extends along the first direction X 1 when viewed in the thickness direction Z 1 .

As shown in FIG. 10 , the bonding layer 5 is interposed between the electronic element 41 and the wiring pattern 3 . A part of the bonding layer 5 is filled in the opening 39 . In the first embodiment, the bonding layer 5 is made of a conductive material. The bonding layer 5 is derived from, e.g., silver paste. Unlike the first embodiment, the bonding layer 5 may be made of an insulating material. In the first embodiment, the bonding layer 5 is in contact with (or in close contact with) a side surface 411 of the electronic element 41 , the first inner side surface 311 of the die pad portion 31 , and a front surface 312 of the die pad portion 31 . This allows the bonding layer 5 to hold the electronic element 41 more firmly. The height of the bonding layer 5 from the main surface 11 is greater than the height of the die pad portion 31 from the main surface 11 . A front surface 51 of the bonding layer 5 is located farther from the main surface 11 than the front surface 312 of the die pad portion 31 .

The protective layer 6 is made of an insulating material. The protective layer 6 may be sometimes referred to as a resist layer. The protective layer 6 is formed on the main surface 11 and the wiring pattern 3 . As shown in FIGS. 3 and 4 , the protective layer 6 is interposed between the base 1 and the resin portion 7 and is in contact with the base 1 and the resin portion 7 .

The protective layer 6 includes portions 61 and 62 . The portions 61 and 62 extend along the second direction Y 1 . The portions 61 and 62 extend from one end of the main surface 11 to the other end thereof in the second direction Y 1 . A part of the portion 61 is formed on the first connecting portion 36 A. A part of the portion 62 is formed on the second connecting portion 36 B.

As shown in FIG. 5 , in the first embodiment, the width W 32 of the narrowest part of the first conductive portion 32 is smaller than any one of the width W 35 A of the first edge portion 35 A, the width W 36 A of the first connecting portion 36 A, and the width W 61 of the portion 61 of the protective layer 6 . In the first embodiment, the width W 35 A of the first edge portion 35 A and the width W 61 of the portion 61 of the protective layer 6 are smaller than the width W 36 A of the first connecting portion 36 A. In the first embodiment, the width W 34 of the wire bonding pad portion 34 is larger than any one of the width W 35 B of the second edge portion 35 B, the width W 36 C of the conductive portion 36 C, and the width W 62 of the portion 62 of the protective layer 6 . In the first embodiment, the width W 36 C of the conductive portion 36 C is smaller than any one of the width W 35 B of the second edge portion 35 B, the width W 36 B of the second connecting portion 36 B, and the width W 62 of the portion 62 of the protective layer 6 . In the first embodiment, the width W 34 of the wire bonding pad portion 34 is smaller than the width W 36 A of the first connecting portion 36 A.

The resin portion 7 covers the base 1 , the electronic element 41 , the wiring pattern 3 , the protective layer 6 , and the wire 42 . In the first embodiment, the resin portion 7 is made of resin that transmits light, such as transparent or translucent epoxy resin, silicone resin, acrylic resin, polyvinyl resin, or the like. The resin portion 7 may include a fluorescent material which emits light of different wavelengths when excited by light from the electronic element 41 . In the first embodiment, unlike a case where the resin portion is a so-called black resin, no filler is mixed in the resin portion 7 . As shown in FIGS. 1 to 4 and so on, the resin portion 7 includes an edge 71 . The edge 71 of the resin portion 7 extends along the second direction Y 1 . The edge 71 extends from one end of the electronic device A 1 to the other end thereof in the second direction Y 1 .

The resin portion 7 is formed by molding. The resin portion 7 is smaller than the base 1 in the first direction X 1 . In the first embodiment, the resin portion 7 has a truncated quadrangular pyramid shape. The resin portion 7 is not limited to the truncated quadrangular pyramid shape but may have a hemispherical shape protruding in the thickness direction Z 1 of the base 1 or may have a concave surface on the front side in the thickness direction Z 1 of the base 1 . Unlike the first embodiment, a reflector surrounding the resin portion 7 and the electronic element 41 may be disposed on the base 1 .

Next, a method of manufacturing the electronic device A 1 according to the first embodiment will be described with reference to FIGS. 11 to 13 . In the first embodiment, a case of manufacturing a plurality of electronic devices A 1 will be described as an example. In the following description, the same or similar elements, portions and parts as above are denoted by the same reference numerals.

First, a rectangular base 100 (see FIG. 11 ) in which a plurality of through-holes 16 are formed in a matrix is prepared. The base 100 has such a size that a plurality of bases 1 shown in FIG. 2 and so on can be formed. A plurality of circular through-holes 16 are formed in the base 100 . The base 100 is made of the same material (that is to say, glass epoxy resin) as the base 1 . Next, the wiring pattern 3 is formed on the base 100 . The wiring pattern 3 is formed by plating Au on a Cu foil. The opening 39 is formed in the wiring pattern 3 .

Next, as shown in FIG. 12 , the bonding layer 5 is formed on the wiring pattern 3 . A portion of the bonding layer 5 is filled in the opening 39 of the wiring pattern 3 .

Next, as shown in FIG. 13 , the protective layer 6 is formed on the base 100 with the wiring pattern 3 formed thereon. In the first embodiment, a film-shaped resist is pressed and adhered to the base 100 .

Next, as shown in FIG. 13 , the electronic element 41 is disposed on the wiring pattern 3 via the bonding layer 5 . Next, the wire 42 is wire-bonded to the electronic element 41 and the wiring pattern 3 . Thus, the electronic elements 41 and the wiring pattern 3 are electrically interconnected.

Next, although not shown, after the resin portion 7 is formed by molding, a plurality of electronic devices A 1 shown in FIG. 1 and so on are produced by dicing an intermediate product on which the resin portion 7 is formed. In the method of manufacturing the electronic device A 1 , a case of manufacturing a plurality of electronic devices A 1 all at once has been illustrated above, but they may be manufactured one by one.

Next, operations and effects of the first embodiment will be described.

In the first embodiment, the opening 39 is formed in the wiring pattern 3 . The bonding layer 5 is in contact with the portion 119 of the base 1 exposed by the opening 39 in the wiring pattern 3 . With such a configuration, since the bonding strength between the bonding layer 5 and the base 1 is strong, it is possible to prevent the bonding layer 5 from being peeled from the base 1 and the wiring pattern 3 .

The bonding strength between the bonding layer 5 and the base 1 is greater than the bonding force between the bonding layer 5 derived from silver paste and the Au plating in the wiring pattern 3 . Therefore, in the embodiment in which the bonding layer 5 is derived from silver paste and the wiring pattern 3 includes the Au plating, it is possible to more effectively prevent the bonding layer 5 from being peeled from the base 1 and the wiring pattern 3 .

In the case where no filler is mixed in the resin portion 7 as in the first embodiment, the resin portion 7 is likely to absorb water. In this case, water vapor may be accumulated at the interface between the resin portion 7 and the base 1 and at the interface between the resin portion 7 and the wiring pattern 3 , possibly causing a water vapor explosion. Even in such a case, in this embodiment, since the bonding layer 5 in contact with the resin portion 7 is firmly bonded to the base 1 , it is possible to prevent the bonding layer 5 from being peeled from the wiring pattern 3 .

In the first embodiment, the wiring pattern 3 includes the first conductive portion 32 . The opening 39 is located between the first conductive portion 32 and the die pad portion 31 when viewed in the thickness direction Z 1 of the base 1 . With such a configuration, in manufacturing the electronic device A 1 , a material making up the bonding layer 5 can be stored in the opening 39 . Therefore, when the electronic element 41 is disposed on the wiring pattern 3 , it is possible to make it easy for the material making the bonding layer 5 to seep up to the electronic element 41 . This is suitable to secure electrical conduction between the electronic element 41 and the wiring pattern 3 more favorably when the bonding layer 5 has conductivity. Further, by storing the material making up the bonding layer 5 in the opening 39 , it is possible to prevent the material making up the bonding layer 5 from flowing into the wire bonding pad portion 34 . As a result, it is possible to prevent defective bonding of the wire 42 to the wire bonding pad portion 34 .

In the first embodiment, the front surface 322 of the first conductive portion 32 includes the exposed part 322 B exposed from the bonding layer 5 . The contact part 322 A is located between the exposed part 322 B and the opening 39 when viewed in the thickness direction Z 1 of the base 1 . With such a configuration, when the electronic element 41 is a light emitting element, light from the light emitting element can be reflected by the exposed part 322 B. Therefore, when the electronic element 41 is a light emitting element, light from the light emitting element can be emitted outside of the electronic device A 1 with higher efficiency.

During a flow of manufacture of the electronic device A 1 , heat is transferred from the first edge portion 35 A side to the first conductive portion 32 via the first connecting portion 36 A. In the first embodiment, the second conductive portion 33 is disposed on a side opposite the first edge portion 35 A with respect to the die pad portion 31 . This makes it possible to minimize the transfer of heat from the first conductive portion 32 to the die pad portion 31 via the second conductive portion 33 .

In the electronic device A 1 , element adhesion strength of a chip mounting portion is strong, but since the outermost surface of a ring-shaped or horn-shaped portion (the first conductive portion 32 ) located outside a circumference thereof is gold-plated, it is likely to peel from the bonding layer 5 . This may make it difficult only for the electronic element 41 to be pulled upward.

Second Embodiment

A second embodiment will be described with reference to FIG. 14 .

FIG. 14 is a plan view of an electronic device A 2 according to a second embodiment in which a resin portion is excluded from the electronic device.

In the following description, the same or similar elements, portions and parts as above are denoted by the same reference numerals and explanation thereof will not be repeated as appropriate.

In the second embodiment, the outer shape of the first conductive portion 32 and the specific shape of the protective layer 6 are different from those of the electronic device A 1 . In the second embodiment, the outer shape of the first conductive portion 32 is a circular shape. In addition, the protective layer 6 includes a portion 63 formed on the first connecting portion 36 A. The portion 63 extends along the same direction (the first direction X 1 ) as the extending direction of the first connecting portion 36 A. The position of a wire bonding pad portion 34 A deviates from the position of the wire bonding pad portion 34 of the first embodiment in the second direction Y 1 . The wire bonding pad portion 34 A is connected to a portion 34 B. The description of the wire bonding pad portion 34 of the first embodiment may be applied for the portion 34 B.

In the second embodiment, the wire bonding pad portion 34 A includes edges 341 to 344 . The edge 341 is connected to the portion 34 B and extends substantially along the first direction X 1 (strictly speaking, a direction inclined to the first direction X 1 ). The edge 342 is connected to the edge 341 and extends substantially along the second direction Y 1 (strictly speaking, a direction inclined to the second direction Y 1 ). The edge 343 is connected to the edge 342 and extends along the first direction X 1 . The edge 344 is connected to the edge 343 and extends substantially along the second direction Y 1 (strictly speaking, a direction inclined to the second direction Y 1 ). The edge 344 is connected to the portion 34 B.

The second embodiment has the following advantages in addition to the advantages described in the first embodiment. During a flow of manufacture of the electronic device A 2 , heat is transferred from the first edge portion 35 A side to the first conductive portion 32 via the first connecting portion 36 A. However, since the portion 61 of the protective layer 6 is formed on the first connecting portion 36 A, the resin portion 7 is bonded to the portion 61 on the first connecting portion 36 A. This makes it possible to prevent the resin portion 7 from being peeled from the wiring pattern 3 on the first connecting portion 36 A.

According to the second embodiment, the wire bonding pad portion 34 A is disposed at a position deviating from the electronic element 41 in the second direction Y 1 . Therefore, it is possible to secure a larger distance between two bonding positions of the wire 42 while suppressing an increase in the area of the main surface 11 . As a result, it is possible to improve the reliability of the connection of the wire 42 while reducing the area of the main surface 11 . As one of the reasons, for example, compared to a case where the wire bonding pad portion 34 A is not disposed at a position deviating from the electronic element 41 in the second direction Y 1 , it is possible to suppress increase in distance in the first direction X 1 (this can cause an increase in area of the main surface 11 ) as much as possible while increasing the distance between the electronic element 41 and the wire bonding pad portion 34 A for wire bonding.

According to the second embodiment, a portion of the wire 42 overlaps with the opening 39 when viewed from a top view. This makes it possible to reduce parasitic capacitance that may occur between the wire 42 and the wiring pattern 3 . As a result, it is possible to control the electronic element 41 with higher accuracy.

Third Embodiment

Next, a third embodiment will be described with reference to FIG. 15 .

FIG. 15 is a plan view of an electronic device A 3 according to a third embodiment in which a resin portion is excluded from the electronic device.

In the following description, the same or similar elements, portions and parts as above are denoted by the same reference numerals and explanation thereof will not be repeated as appropriate.

The third embodiment is different from the first embodiment in that the wiring pattern 3 includes a plurality of second conductive portions 33 . Each of the plurality of second conductive portions 33 radially extends from the die pad portion 31 . The opening 39 in the wiring pattern 3 has a plurality of portions 391 separated from each other. The configuration of the third embodiment may be combined with the configuration of the second embodiment.

The third embodiment is particularly suitable, for example, when the size of the electronic element 41 is larger than the size in the first embodiment.

According to the third embodiment, a portion of the wire 42 overlaps with the opening 39 when viewed from a top view. This makes it possible to reduce parasitic capacitance that may occur between the wire 42 and the wiring pattern 3 . As a result, it is possible to control the electronic element 41 with higher accuracy.

The present disclosure is not limited to the above-described embodiments. The specific configurations of various portions and parts of the present disclosure can be changed in design in different ways.

Variations of the above-described embodiments will be supplemented as follows.

[Supplementary Note 1]

An electronic device including: a base; a wiring pattern formed on the base; an electronic element disposed on the wiring pattern; and a bonding layer interposed between the electronic element and the wiring pattern, wherein an opening is formed in the wiring pattern and the bonding layer is in contact with a portion of the base exposed by the opening in the wiring pattern.

[Supplementary Note 2]

The electronic device of Supplementary Note 1, wherein the wiring pattern includes a die pad portion on which the electronic element is disposed, a part of the die pad portion defines the opening, and the bonding layer is in contact with the die pad portion.

[Supplementary Note 3]

The electronic device of Supplementary Note 2, wherein the die pad portion includes a first inner side surface facing a direction intersecting a thickness direction of the base, the first inner side surface defines a portion of the opening, and the bonding layer is in contact with the first inner side surface.

[Supplementary Note 4]

The electronic device of Supplementary Note 3, wherein the wiring pattern includes a first conductive portion and the opening is located between the first conductive portion and the die pad portion when viewed in the thickness direction of the base.

[Supplementary Note 5]

The electronic device of Supplementary Note 4, wherein the first conductive portion includes a second inner side surface facing the first inner side surface and the bonding layer is in contact with the second inner side surface.

[Supplementary Note 6]

The electronic device of Supplementary Note 4 or 5, wherein the first conductive portion includes a front surface facing the thickness direction of the base and the front surface of the first conductive portion includes a contact part in contact with the bonding layer.

[Supplementary Note 7]

The electronic device of Supplementary Note 6, wherein the surface of the first conductive portion includes an exposed part exposed from the bonding layer and the contact part is located between the exposed part and the opening when viewed in the thickness direction of the base.

[Supplementary Note 8]

The electronic device of any one of Supplementary Notes 4 to 7, wherein the first conductive portion has an annular shape surrounding the die pad portion.

[Supplementary Note 9]

The electronic device of Supplementary Note 4, wherein the wiring pattern includes one or more second conductive portions connected to both the die pad portion and the first conductive portion, each of the one or more second conductive portions is located between the die pad portion and the first conductive portion, a part of one of the one or more second conductive portions defining the opening, and the bonding layer is in contact with the one or more second conductive portions.

[Supplementary Note 10]

The electronic device of Supplementary Note 9, wherein each of the one or more second conductive portions extends from the die pad portion toward the first conductive portion when viewed in the thickness direction of the base and has a front surface facing the thickness direction of the base, and the front surface of each of the one or more second conductive portions is in contact with the bonding layer.

[Supplementary Note 11]

The electronic device of Supplementary Note 10, wherein the die pad portion includes a first edge and a second edge located on opposite sides in the die pad portion when viewed in the thickness direction of the base, and a width of each of the one or more second conductive portions is smaller than a separation distance between the first edge and the second edge.

[Supplementary Note 12]

The electronic device of any one of Supplementary Notes 1 to 11, wherein the electronic element is an optical element or a zener diode.

[Supplementary Note 13]

The electronic device of Supplementary Note 4, further including a wire bonded to the electronic element, wherein the wiring pattern includes a wire bonding pad portion to which the wire is bonded.

[Supplementary Note 14]

The electronic device of Supplementary Note 13, wherein the base has a main surface and a back surface opposing each other, the electronic element is disposed on the main surface, and the wiring pattern is formed on the main surface and the back surface.

[Supplementary Note 15]

The electronic device of Supplementary Note 14, wherein the base has a first side surface and a second side surface facing a direction perpendicular to the thickness direction of the base, the first side surface and the second side surface opposing each other, wherein a first concave portion recessed from the first side surface and a second concave portion recessed from the second side surface are formed in the base, wherein the wiring pattern includes a first connecting portion, a second connecting portion, a first edge portion, a second edge portion, a first side surface portion, and a second side surface portion, wherein the first edge portion is formed on the main surface and extends along an edge of the first concave portion, wherein the second edge portion is formed on the main surface and extends along an edge of the second concave portion, wherein the first side surface portion is formed on an inner side surface of the first concave portion and is connected to the first edge portion, wherein the second side surface portion is formed on an inner side surface of the second concave portion and is connected to the second edge portion, wherein the first connecting portion is formed on the main surface, is located between the first conductive portion and the first edge portion, and is electrically connected to the first conductive portion and the first edge portion, and wherein the second connecting portion is formed on the main surface, is located between the wire bonding pad portion and the second edge portion, and is electrically connected to the wire bonding pad portion and the second edge portion.

[Supplementary Note 16]

The electronic device of any one of Supplementary Notes 1 to 15, further including a resin portion covering the electronic element, the wiring pattern, and the base.

[Supplementary Note 17]

The electronic device of Supplementary Note 15, further including a protective layer covering the wiring pattern, wherein the protective layer includes a portion covering the first connecting portion.

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosures. Indeed, the embodiments described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the disclosures. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the disclosures.